#!/bin/sh

# define default configuration
POLL=true
SMP=auto
ERL_MAX_PORTS=32000
ERL_PROCESSES=250000
ERL_MAX_ETS_TABLES=1400

# define default environment variables
NODE=ejabberd
HOST=localhost
ERLANG_NODE=$NODE@$HOST
ERL=/usr/local/bin/erl
INSTALLUSER=

# parse command line parameters
ARGS=
while [ $# -ne 0 ] ; do
    PARAM=$1
    shift
    case $PARAM in
        --) break ;;
        --node) ERLANG_NODE_ARG=$1; shift ;;
        --config-dir) ETCDIR=$1 ; shift ;;
        --config) EJABBERD_CONFIG_PATH=$1 ; shift ;;
        --ctl-config) EJABBERDCTL_CONFIG_PATH=$1 ; shift ;;
        --logs) LOGS_DIR=$1 ; shift ;;
        --spool) SPOOLDIR=$1 ; shift ;;
        *) ARGS="$ARGS $PARAM" ;;
    esac
done

# Define ejabberd variable if they have not been defined from the command line
if [ "$ETCDIR" = "" ] ; then
    ETCDIR=//etc/ejabberd
fi
if [ "$EJABBERD_CONFIG_PATH" = "" ] ; then
    EJABBERD_CONFIG_PATH=$ETCDIR/ejabberd.cfg
fi
if [ "$EJABBERDCTL_CONFIG_PATH" = "" ] ; then
    EJABBERDCTL_CONFIG_PATH=$ETCDIR/ejabberdctl.cfg
fi
[ -f "$EJABBERDCTL_CONFIG_PATH" ] && . "$EJABBERDCTL_CONFIG_PATH"
if [ "$LOGS_DIR" = "" ] ; then
    LOGS_DIR=//var/log/ejabberd
fi
if [ "$SPOOLDIR" = "" ] ; then
    SPOOLDIR=//var/lib/ejabberd
fi
if [ "$EJABBERD_DOC_PATH" = "" ] ; then
    EJABBERD_DOC_PATH=//share/doc/ejabberd
fi
if [ "$ERLANG_NODE_ARG" != "" ] ; then
    ERLANG_NODE=$ERLANG_NODE_ARG
fi

# check the proper system user is used
ID=`id -g`
GIDS=`id -G`
EJID=`id -g $INSTALLUSER`
EXEC_CMD="false"
for GID in $GIDS; do
    if [ $GID -eq 0 ] ; then
	EXEC_CMD="su ${INSTALLUSER} -p -c"
    fi
done
if [ "$ID" -eq "$EJID" ] ; then
	EXEC_CMD="sh -c"
fi
if [ "$EXEC_CMD" = "false" ] ; then
	echo "This command can only be run by root or the user $INSTALLUSER" >&2
	exit 4
fi

NAME=-name
[ "$ERLANG_NODE" = "${ERLANG_NODE%.*}" ] && NAME=-sname

if [ "$FIREWALL_WINDOW" = "" ] ; then
    KERNEL_OPTS=""
else
    KERNEL_OPTS="-kernel inet_dist_listen_min ${FIREWALL_WINDOW%-*} inet_dist_listen_max ${FIREWALL_WINDOW#*-}"
fi

ERLANG_OPTS="+K $POLL -smp $SMP +P $ERL_PROCESSES $ERL_OPTIONS $KERNEL_OPTS"

# define additional environment variables
if [ "$EJABBERDDIR" = "" ]; then
    EJABBERDDIR=//lib/ejabberd
fi
if [ "$EJABBERD_EBIN_PATH" = "" ]; then
    EJABBERD_EBIN_PATH=$EJABBERDDIR/ebin
fi
if [ "$EJABBERD_PRIV_PATH" = "" ]; then
    EJABBERD_PRIV_PATH=$EJABBERDDIR/priv
fi
if [ "$EJABBERD_BIN_PATH" = "" ]; then
    EJABBERD_BIN_PATH=$EJABBERD_PRIV_PATH/bin
fi
if [ "$EJABBERD_SO_PATH" = "" ]; then
    EJABBERD_SO_PATH=$EJABBERD_PRIV_PATH/lib
fi
if [ "$EJABBERD_MSGS_PATH" = "" ]; then
    EJABBERD_MSGS_PATH=$EJABBERD_PRIV_PATH/msgs
fi

EJABBERD_LOG_PATH=$LOGS_DIR/ejabberd.log
SASL_LOG_PATH=$LOGS_DIR/erlang.log
DATETIME=`date "+%Y%m%d-%H%M%S"`
ERL_CRASH_DUMP=$LOGS_DIR/erl_crash_$DATETIME.dump
ERL_INETRC=$ETCDIR/inetrc
HOME=$SPOOLDIR

# create the home dir with the proper user if doesn't exist, because it stores cookie file
[ -d $HOME ] || $EXEC_CMD "mkdir -p $HOME"

# export global variables
export EJABBERD_CONFIG_PATH
export EJABBERD_MSGS_PATH
export EJABBERD_LOG_PATH
export EJABBERD_SO_PATH
export EJABBERD_BIN_PATH
export EJABBERD_DOC_PATH
export EJABBERD_PID_PATH
export ERL_CRASH_DUMP
export ERL_INETRC
export ERL_MAX_PORTS
export ERL_MAX_ETS_TABLES
export HOME
export EXEC_CMD


# Compatibility in ZSH
#setopt shwordsplit 2>/dev/null

# start server
start ()
{
    $EXEC_CMD "$ERL \
      $NAME $ERLANG_NODE \
      -noinput -detached \
      -pa $EJABBERD_EBIN_PATH \
      -mnesia dir \"\\\"$SPOOLDIR\\\"\" \
      -s ejabberd \
      -sasl sasl_error_logger \\{file,\\\"$SASL_LOG_PATH\\\"\\} \
      $ERLANG_OPTS $ARGS \"$@\""
}

# attach to server
debug ()
{
    echo "--------------------------------------------------------------------"
    echo ""
    echo "IMPORTANT: we will attempt to attach an INTERACTIVE shell"
    echo "to an already running ejabberd node."
    echo "If an ERROR is printed, it means the connection was not successful."
    echo "You can interact with the ejabberd node if you know how to use it."
    echo "Please be extremely cautious with your actions,"
    echo "and exit immediately if you are not completely sure."
    echo ""
    echo "To detach this shell from ejabberd, press:"
    echo "  control+c, control+c"
    echo ""
    echo "--------------------------------------------------------------------"
    echo "To bypass permanently this warning, add to ejabberdctl.cfg the line:"
    echo "  EJABBERD_BYPASS_WARNINGS=true"
    echo "Press any key to continue"
    if [ "$EJABBERD_BYPASS_WARNINGS" != "true" ] ; then
	read foo
    fi
    echo ""
    TTY=`tty | sed -e  's/.*\///g'`
    $EXEC_CMD "$ERL \
      $NAME debug-${TTY}-${ERLANG_NODE} \
      -remsh $ERLANG_NODE \
      -hidden \
      $ERLANG_OPTS $ARGS \"$@\""
}

# start interactive server
live ()
{
    echo "--------------------------------------------------------------------"
    echo ""
    echo "IMPORTANT: ejabberd is going to start in LIVE (interactive) mode."
    echo "All log messages will be shown in the command shell."
    echo "You can interact with the ejabberd node if you know how to use it."
    echo "Please be extremely cautious with your actions,"
    echo "and exit immediately if you are not completely sure."
    echo ""
    echo "To exit this LIVE mode and stop ejabberd, press:"
    echo "  q().  and press the Enter key"
    echo ""
    echo "--------------------------------------------------------------------"
    echo "To bypass permanently this warning, add to ejabberdctl.cfg the line:"
    echo "  EJABBERD_BYPASS_WARNINGS=true"
    echo "Press any key to continue"
    if [ "$EJABBERD_BYPASS_WARNINGS" != "true" ] ; then
	read foo
    fi
    echo ""
    $EXEC_CMD "$ERL \
      $NAME $ERLANG_NODE \
      -pa $EJABBERD_EBIN_PATH \
      -mnesia dir \"\\\"$SPOOLDIR\\\"\" \
      -s ejabberd \
      $ERLANG_OPTS $ARGS \"$@\""
}

help ()
{
    echo ""
    echo "Commands to start an ejabberd node:"
    echo "  start  Start an ejabberd node in server mode"
    echo "  debug  Attach an interactive Erlang shell to a running ejabberd node"
    echo "  live   Start an ejabberd node in live (interactive) mode"
    echo ""
    echo "Optional parameters when starting an ejabberd node:"
    echo "  --config-dir dir   Config ejabberd:    $ETCDIR"
    echo "  --config file      Config ejabberd:    $EJABBERD_CONFIG_PATH"
    echo "  --ctl-config file  Config ejabberdctl: $EJABBERDCTL_CONFIG_PATH"
    echo "  --logs dir         Directory for logs: $LOGS_DIR"
    echo "  --spool dir        Database spool dir: $SPOOLDIR"
    echo "  --node nodename    ejabberd node name: $ERLANG_NODE"
    echo ""
}

# common control function
ctl ()
{
    COMMAND=$@

    # Control number of connections identifiers
    # using flock if available. Expects a linux-style
    # flock that can lock a file descriptor.
    MAXCONNID=100
    CONNLOCKDIR=//var/lock/ejabberdctl
    FLOCK='/usr/bin/flock'
    if [ ! -x "$FLOCK" ] ; then
	JOT='/usr/bin/jot'
	if [ ! -x "$JOT" ] ; then
	    # no flock or jot, simply invoke ctlexec()
	    CTL_CONN="ctl-${ERLANG_NODE}"
	    ctlexec $CTL_CONN $COMMAND
	    result=$?
	else
	    # no flock, but at least there is jot
	    RAND=`jot -r 1 0 $MAXCONNID`
	    CTL_CONN="ctl-${RAND}-${ERLANG_NODE}"
	    ctlexec $CTL_CONN $COMMAND
	    result=$?
	fi
    else
	# we have flock so we get a lock
	# on one of a limited number of
	# conn names -- this allows
	# concurrent invocations using a bound
	# number of atoms
	for N in $(seq 1 $MAXCONNID); do
	    CTL_CONN="ejabberdctl-$N"
	    CTL_LOCKFILE="$CONNLOCKDIR/$CTL_CONN"
	    (
		exec 8>"$CTL_LOCKFILE"
		if flock --nb 8; then
		    ctlexec $CTL_CONN $COMMAND
                    ssresult=$?
                    # segregate from possible flock exit(1)
		    ssresult=$(expr $ssresult \* 10)
		    exit $ssresult
		else
		    exit 1
		fi
            )
	    result=$?
	    if [ $result -eq 1 ]; then
                # means we errored out in flock
                # rather than in the exec - stay in the loop
                # trying other conn names...
		badlock=1
	    else
		badlock=""
		break;
	    fi
	done
	result=$(expr $result / 10)
    fi

    if [ "$badlock" ];then
	echo "Ran out of connections to try. Your ejabberd processes" >&2
	echo "may be stuck or this is a very busy server. For very"   >&2
	echo "busy servers, consider raising MAXCONNID in ejabberdctl">&2
	exit 1;
    fi

    case $result in
	0) :;;
	1) :;;
	2) help;;
	3) help;;
    esac
    return $result
}

ctlexec ()
{
    CONN_NAME=$1; shift
    COMMAND=$@
    $EXEC_CMD "$ERL \
      $NAME ${CONN_NAME} \
      -noinput \
      -hidden \
      -pa $EJABBERD_EBIN_PATH \
      -s ejabberd_ctl -extra $ERLANG_NODE $COMMAND"
}

# display ctl usage
usage ()
{
    ctl
    exit
}

# stop epmd if there is no other running node
stop_epmd()
{
    epmd -names | grep -q name || epmd -kill
}

# allow sync calls
wait_for_status()
{
    # args: status try delay
    # return: 0 OK, 1 KO
    timeout=$2
    status=4
    while [ $status -ne $1 ]; do
        sleep $3
        timeout=$(($timeout - 1))
        [ $timeout -eq 0 ] && {
            status=$1
        } || {
            ctl status > /dev/null
            status=$?
        }
    done
    [ $timeout -eq 0 ] && {
        status=1
    } || {
        status=0
    }
    return $status
}

case $ARGS in
    ' start') start;;
    ' debug') debug;;
    ' live') live;;
    ' started') wait_for_status 0 30 2;; # wait 30x2s before timeout
    ' stopped') wait_for_status 3 15 2; stop_epmd;; # wait 15x2s before timeout
    *) ctl $ARGS;;
esac
